Air India — delay in connecting flight leading to flight cancellation and no refund from air india

Address:

New Delhi, Delhi

I has booked my Delhi- Bengaluru- Hubli for 14.03.2019 and for back (on 17.03.2019) flight tickets through Air India website on 5th MArch 2019. Since there was no direct flight to Hubli from Delhi, I had to book ticket through connecting flight at Bangalore. Unfortunately my Hubli to Bengaluru Flight which was scheduled for departure at 4 pm on 17.03.2019 was delayed by several hours due to which it was not possible for me to catch the connecting flight from Bengaluru to Delhi at 09.00 PM, and thus i was forced to cancel my Hubli to Bengaluru Flight and i travel via road to Bengaluru to catch the connecting flight timely. I contacted to customer care of Air India and i was told that i will get the refund for cancelled flight within a week as delay was on part of Air India. But i didn't get any refund till date inspite of several calls and emails to Air India.
Your are requested to please lodged my complaint and help me to get the refund from Air India as i have sent several emails but they are not bothering for that.
Image of the ticket is attached for your kind reference